Scientists Successfully 'Reset' Stem Cells

Scientists have successfully "reset" stem cells in the lab to a fully pristine state, according to new breakthrough research that can transform the world of medicine.

Embryonic stem cells are capable of differentiating into any type of cell, and until now researchers have only been able to transform "adult" human cells into pluripotent stem cells. Not to mention that these adult cells possess different properties than embryonic cells, predisposing them to become specific cell types rather than maintaining a host of other possibilities.

So far, authentic embryonic stem cells have only been derived from mice and rats.

"Reverting mouse cells to a completely 'blank slate' has become routine, but generating equivalent naïve human cell lines has proven far more challenging," Dr. Paul Bertone, Research Group Leader at EMBL-EBI and a senior author on the study, said in a statement. "Human pluripotent cells resemble a cell type that appears slightly later in mammalian development, after the embryo has implanted in the uterus."

At this point subtle changes in gene expression begin to influence the cells, which are then considered "primed" towards a particular lineage. Although pluripotent human cells can be cultured from in vitro fertilized (IVF) embryos, until now there have been no human cells comparable to those obtained from the mouse.

"For years, it was thought that we could be missing the developmental window when naïve human cells could be captured, or that the right growth conditions hadn't been found," Paul explained.

The researchers decided to take a different approach, using the genes NANOG and KLF2 to reset the cells. By inhibiting certain biological pathways, they were able to effectively turn these embryonic stem cells into blank slates, capable of turning into any type of cell.

"Our findings suggest that it is possible to rewind the clock to achieve true ground-state pluripotency in human cells," said research collaborator Austin Smith. "These cells may represent the real starting point for formation of tissues in the human embryo. We hope that in time they will allow us to unlock the fundamental biology of early development, which is impossible to study directly in people."

The findings were published in the journal Cell.